In 1998, Section 508 of the amended Rehabilitation Act (29 USC 794d) required Federal agencies to make electronic and information technology accessible to individuals with disabilities. The law applies to all Federal agencies that develop, procure, maintain, or use electronic and information technology. Since inaccessible technology interferes with a disabled individual's ability to obtain and use information quickly and easily, it is necessary to eliminate barriers in technology posed to individuals with disabilities. For example, when colors are the sole method for indicating the status of a device's elements or controls, colorblind people may find the device difficult to use. Accordingly, devices must provide another method of status indication, such as text labels or shape-coding, combined with the use of color.
A wide variety of electronic devices, such as business telephones, have traditionally used single-color Light Emitting Diodes or LEDs to convey status information. For example, an illuminated green LED might indicate that the corresponding line is available, while an illuminated red LED, associated with the same line, might indicate that the line is busy. Although color is used to convey information, this has not been a problem for colorblind users because the two LEDs are readily discernible to be in different locations. Illustratively, for the colorblind user, the line is available when the LED on the left is illuminated, and is busy when the LED on the right is illuminated.
A bi-color LED is composed of a pair of differently colored LEDs within the same housing. In a typical configuration, when a DC current flows in one direction through the bi-color LED, a first LED of a first color (but not a second LED of a different second color) is illuminated to provide the first color and, when the DC current flows in the opposing direction, the second but not the first LED is illuminated to provide the second color. Bi-color LEDs are often preferred in place of separate multiple single-color LEDs for a variety of reasons; these include a significant reduction in the cost of associated printed circuit boards, and an ability to miniaturize the display and user interface of the associated device. A problem, of course, is that the co-location of different-color emitters within the same LED housing makes it impossible for colorblind users to interpret the information that is being conveyed. Accordingly, such devices are not in compliance with federal procurement requirements.
An inexpensive space-saving solution, that would allow colorblind people to discern the status of bi-color LEDs, would be valuable and beneficial.